LEP and thyroid cancer: Nevertheless, our results are in agreement with several other reports which have documented that immunoexpression of leptin is linked with one or more of the clinical factors such as tumor stage, infiltration, metastasis, relapse, therapy resistance and bad prognostic outcomes of several tumors including laryngeal cancer [41], esophageal cancer [42], stomach cancer [43], lung cancer [44], and thyroid cancer [45].